The present invention relates to a track-bound electric motor vehicle and improved driving means therefor.
European Patent Application Publication No. 0 005 777 discloses a track-bound electric motor vehicle having electric traction motors which drive respective driving wheels of the vehicle via gears and in which both driving wheels of an axle are fastened to separate shaft sections guided relative to each other and forming a driving axle.
The two driving wheels of an axle of the electric motor vehicle are each driven seperately by an electric traction motor. Each driving wheel is fastened on a hollow shaft and the two hollow shafts are supported on a common rigid stationary shaft. Thereby, mechanical decoupling of the two driving wheels is achieved and the slippage of one of the wheels otherwise occuring in negotiating curves is avoided.
In the vehicle of the aforementioned European patent application, the full speed of rotation of the driving wheels is always present at the support of the hollow shafts on the rigid shaft, which makes use of grease- or oil-lubricated bearings, particularly anti-friction bearings, necessary. Therefore, the outside diameter of the hollow shaft must be made relatively large. Furthermore, no spring or cushioning apparatus is provided for the hollow shaft with the large gear or for the traction motors, which can result in a degrading of the running performance of the vehicle.